Workflow not updating Last Activity Field

Please help:

I’ve created a workflow to update a Contacts “Last Activity” field with the current date and time each time a new call is logged for that Customer. However the update doesn’t seem to be taking place, can someone help me resolve this issue. Attached is a copy of the workflow I have created,

In an attempt to diagnose the issue I’ve done the following;
-Reset the file permissions
-Repair and Rebuild
-Logged out and back in

Is your scheduler running? Do you have the cron job set up?

Yes Cron Jobs are running, verified in the SuiteCRM log

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